关于android中for循环的问题——好奇怪啊？请求大神解答

Question

出现了些问题，以我现在的能力实在找不到原因。
问题如下：for循环当条件部位true时仍继续循环，一直循环到他心情好。
具体情况例for（；x < y；）{}当x>y时仍然在循环，这是什么原因呢，换了while情况依然一样。
具体代码如下，如果没时间就不用看了。请求各位大神告诉小弟原因，还有解决的思路。拜谢了package bnu.ep;import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;public class ReadView extends View { //屏幕宽度
int screenWidth ;
//屏幕高度
int screenHeight ;
//文字大小
int word_Size = 20;
//行距
int Leading = 2;

//当前行数
int Now_LineNumber = 1;
//文字
String str = "jiyuhang 中hangm yujia =lljyhjyhjyjjjmmmqssssmmmmmmskkkjdjh,hdjj，jiyuhang 中hangm ";
//当前文字
int k = 0;
//当前页数
int now_page = 0;
//每页字数
int a[]  = new int[10]; //字符总长度
int word_long = str.length();
// 实例化绘制方法
Paint m_paint = new Paint(Paint.ANTI_ALIAS_FLAG);



public ReadView(Context context) {
super(context);
// TODO Auto-generated constructor stub
setFocusable(true);
}
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//Now_LineNumber = 1;
//每页行数
int line_number = (screenHeight/word_Size) - 1;

//文字大小
m_paint.setTextSize(word_Size);
canvas.drawARGB(255,255,255,255);   
//字符绘制Y坐标
int y = word_Size;
Log.i("screenHeight",""+screenHeight);
Log.i("screenWidth",""+screenWidth); while(this.Now_LineNumber < line_number)
{
String str2 = "";
if(this.k >= word_long||y >= screenHeight)
{  
break;
}
for(;;k++)
{
//Log.i("k",""+k);
if(k < word_long)
{
str2 += str.substring(k,k+1);
}
else
{
break;
}
float textWidth = m_paint.measureText(str2);
if(textWidth >= screenWidth)
{
if(textWidth > screenWidth)
{
int beyond_long = str2.length();
str2 = str2.substring(0,beyond_long - 1);
break;
}
break;
}
}
//绘制文字
canvas.drawText(str2, 0, y, m_paint);
//y坐标每次增加字符高度（即字体大小+行距）
y =  y + word_Size + Leading;
Now_LineNumber++;
}
}}用的是全局变量，现在那个for改成while。

Answer 1

把代码放在[/code] 之前，放在[code=Java]之后

Answer 2

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;public class ReadView extends View {//屏幕宽度
int screenWidth ;
//屏幕高度
int screenHeight ;
//文字大小
int word_Size = 20;
//行距
int Leading = 2;//当前行数
int Now_LineNumber = 1; 
//文字
String str = "jiyuhang 中hangm yujia =lljyhjyhjyjjjmmmqssssmmmmmmskkkjdjh,hdjj，jiyuhang 中hangm ";
//当前文字
int k = 0;
//当前页数
int now_page = 0;
//每页字数
int a[] = new int[10];//字符总长度
int word_long = str.length();
// 实例化绘制方法
Paint m_paint = new Paint(Paint.ANTI_ALIAS_FLAG);public ReadView(Context context) {
super(context);
// TODO Auto-generated constructor stub
setFocusable(true);
}
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//Now_LineNumber = 1;
//每页行数
int line_number = (screenHeight/word_Size) - 1;//文字大小
m_paint.setTextSize(word_Size);
canvas.drawARGB(255,255,255,255);   
//字符绘制Y坐标
int y = word_Size;
Log.i("screenHeight",""+screenHeight);
Log.i("screenWidth",""+screenWidth);while(this.Now_LineNumber < line_number)
{
String str2 = "";
if(this.k >= word_long||y >= screenHeight)
{   
break;
}
for(;;k++)
{
//Log.i("k",""+k);
if(k < word_long)
{
str2 += str.substring(k,k+1);
}
else
{
break;
}
float textWidth = m_paint.measureText(str2);
if(textWidth >= screenWidth)
{
if(textWidth > screenWidth)
{
int beyond_long = str2.length();
str2 = str2.substring(0,beyond_long - 1);
break;
}
break;
}
}
//绘制文字
canvas.drawText(str2, 0, y, m_paint);
//y坐标每次增加字符高度（即字体大小+行距）
y = y + word_Size + Leading; 
Now_LineNumber++;
}
}}

Answer 3

楼主你这些代码貌似画不出东西来，暂不说for循环的问题

Answer 4

我改了下你的代码
public class ReadActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        int screenWidth = dm.widthPixels;
        int screenHeight = dm.heightPixels;
        ReadView readView = new ReadView(this, screenWidth,  screenHeight);
        setContentView(readView);
    }
}
public class ReadView extends View { // 屏幕宽度
int screenWidth;
// 屏幕高度
int screenHeight;
// 文字大小
int word_Size = 20;
// 行距
int Leading = 2;
// 当前行数
int Now_LineNumber = 1;
// 文字
String str = "jiyuhang 中hangm yujia =lljyhjyhjyjjjmmmqssssmmmmmmskkkjdjh,hdjj，jiyuhang 中hangm ";
// 当前文字
int k = 0;
// 当前页数
int now_page = 0;
// 每页字数
int a[] = new int[10];
// 字符总长度
int word_long = str.length();
// 实例化绘制方法
Paint m_paint; public ReadView(Context context, int width, int height) {
super(context);
// TODO Auto-generated constructor stub
screenWidth = width;
screenHeight = height;
setFocusable(true);
m_paint = new Paint(Paint.ANTI_ALIAS_FLAG);
} protected void onDraw(Canvas canvas) {
super.onDraw(canvas);

// 每页行数
int line_number = (screenHeight / word_Size) - 1; // 文字大小
m_paint.setTextSize(word_Size);
canvas.drawARGB(255, 255, 255, 255);

// 字符绘制Y坐标
int y = 0;
Log.i("screenHeight", "" + screenHeight);
Log.i("screenWidth", "" + screenWidth);
        
while (this.Now_LineNumber < line_number) {
Log.i(">>>>>>>>>>>>>>>>while<<<<<<<<<<<<<<<<", ">>>>>>>>>>>>>>>>>>>loop == true????");
String str2 = "";
if (this.k >= word_long || y >= screenHeight) {
break;
}
for (;; k++) {
 Log.i("KKKKKKKKKK============",""+k);
if (k < word_long) {
str2 += str.substring(k, k + 1);
} else {
break;
}
float textWidth = m_paint.measureText(str2);
if (textWidth >= screenWidth) {
if (textWidth > screenWidth) {
int beyond_long = str2.length();
str2 = str2.substring(0, beyond_long - 1);
break;
}
break;
}
}

// y坐标每次增加字符高度（即字体大小+行距）
y +=  word_Size + Leading;
// 绘制文字
canvas.drawText(str2, 0, y, m_paint);
Now_LineNumber++;
} }}下面是运行的Log，没有出现像楼主说的那样非条件下还循环的问题，Log为证05-28 00:38:03.761: INFO/screenHeight(729): 480
05-28 00:38:03.761: INFO/screenWidth(729): 320
05-28 00:38:03.770: INFO/>>>>>>>>>>>>>>>>while<<<<<<<<<<<<<<<<(729): >>>>>>>>>>>>>>>>>>>loop == true????
05-28 00:38:03.770: INFO/KKKKKKKKKK============(729): 0
05-28 00:38:03.770: INFO/KKKKKKKKKK============(729): 1
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 2
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 3
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 4
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 5
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 6
05-28 00:38:03.780: INFO/KKKKKKKKKK============(729): 7
05-28 00:38:03.801: INFO/KKKKKKKKKK============(729): 8
05-28 00:38:03.801: INFO/KKKKKKKKKK============(729): 9
05-28 00:38:03.850: INFO/KKKKKKKKKK============(729): 10
05-28 00:38:03.850: INFO/KKKKKKKKKK============(729): 11
05-28 00:38:03.861: INFO/KKKKKKKKKK============(729): 12
05-28 00:38:03.861: INFO/KKKKKKKKKK============(729): 13
05-28 00:38:03.880: INFO/KKKKKKKKKK============(729): 14
05-28 00:38:03.880: INFO/KKKKKKKKKK============(729): 15
05-28 00:38:03.880: INFO/KKKKKKKKKK============(729): 16
05-28 00:38:03.891: INFO/KKKKKKKKKK============(729): 17
05-28 00:38:03.901: INFO/KKKKKKKKKK============(729): 18
05-28 00:38:03.901: INFO/KKKKKKKKKK============(729): 19
05-28 00:38:03.910: INFO/KKKKKKKKKK============(729): 20
05-28 00:38:03.920: INFO/KKKKKKKKKK============(729): 21
05-28 00:38:03.920: INFO/KKKKKKKKKK============(729): 22
05-28 00:38:03.931: INFO/KKKKKKKKKK============(729): 23
05-28 00:38:03.931: INFO/KKKKKKKKKK============(729): 24
05-28 00:38:03.941: INFO/KKKKKKKKKK============(729): 25
05-28 00:38:03.941: INFO/KKKKKKKKKK============(729): 26
05-28 00:38:03.951: INFO/KKKKKKKKKK============(729): 27
05-28 00:38:03.951: INFO/KKKKKKKKKK============(729): 28
05-28 00:38:03.960: INFO/KKKKKKKKKK============(729): 29
05-28 00:38:03.960: INFO/KKKKKKKKKK============(729): 30
05-28 00:38:03.971: INFO/KKKKKKKKKK============(729): 31
05-28 00:38:03.971: INFO/KKKKKKKKKK============(729): 32
05-28 00:38:03.971: INFO/KKKKKKKKKK============(729): 33
05-28 00:38:03.981: INFO/KKKKKKKKKK============(729): 34
05-28 00:38:03.981: INFO/KKKKKKKKKK============(729): 35
05-28 00:38:04.001: INFO/>>>>>>>>>>>>>>>>while<<<<<<<<<<<<<<<<(729): >>>>>>>>>>>>>>>>>>>loop == true????
05-28 00:38:04.001: INFO/KKKKKKKKKK============(729): 35
05-28 00:38:04.020: INFO/KKKKKKKKKK============(729): 36
05-28 00:38:04.020: INFO/KKKKKKKKKK============(729): 37
05-28 00:38:04.031: INFO/KKKKKKKKKK============(729): 38
05-28 00:38:04.031: INFO/KKKKKKKKKK============(729): 39
05-28 00:38:04.031: INFO/KKKKKKKKKK============(729): 40
05-28 00:38:04.041: INFO/KKKKKKKKKK============(729): 41
05-28 00:38:04.051: INFO/KKKKKKKKKK============(729): 42
05-28 00:38:04.051: INFO/KKKKKKKKKK============(729): 43
05-28 00:38:04.060: INFO/KKKKKKKKKK============(729): 44
05-28 00:38:04.060: INFO/KKKKKKKKKK============(729): 45
05-28 00:38:04.071: INFO/KKKKKKKKKK============(729): 46
05-28 00:38:04.071: INFO/KKKKKKKKKK============(729): 47
05-28 00:38:04.080: INFO/KKKKKKKKKK============(729): 48
05-28 00:38:04.080: INFO/KKKKKKKKKK============(729): 49
05-28 00:38:04.091: INFO/KKKKKKKKKK============(729): 50
05-28 00:38:04.091: INFO/KKKKKKKKKK============(729): 51
05-28 00:38:04.091: INFO/KKKKKKKKKK============(729): 52
05-28 00:38:04.101: INFO/KKKKKKKKKK============(729): 53
05-28 00:38:04.101: INFO/KKKKKKKKKK============(729): 54
05-28 00:38:04.131: INFO/KKKKKKKKKK============(729): 55
05-28 00:38:04.131: INFO/KKKKKKKKKK============(729): 56
05-28 00:38:04.131: INFO/KKKKKKKKKK============(729): 57
05-28 00:38:04.131: INFO/KKKKKKKKKK============(729): 58
05-28 00:38:04.161: INFO/KKKKKKKKKK============(729): 59
05-28 00:38:04.161: INFO/KKKKKKKKKK============(729): 60
05-28 00:38:04.170: INFO/KKKKKKKKKK============(729): 61
05-28 00:38:04.180: INFO/>>>>>>>>>>>>>>>>while<<<<<<<<<<<<<<<<(729):>>>>>>>>>>>>>>>>>>>loop == true????
05-28 00:38:04.180: INFO/KKKKKKKKKK============(729): 61
05-28 00:38:04.191: INFO/KKKKKKKKKK============(729): 62
05-28 00:38:04.201: INFO/KKKKKKKKKK============(729): 63
05-28 00:38:04.201: INFO/KKKKKKKKKK============(729): 64
05-28 00:38:04.211: INFO/KKKKKKKKKK============(729): 65
05-28 00:38:04.221: INFO/KKKKKKKKKK============(729): 66
05-28 00:38:04.221: INFO/KKKKKKKKKK============(729): 67
05-28 00:38:04.231: INFO/KKKKKKKKKK============(729): 68
05-28 00:38:04.231: INFO/KKKKKKKKKK============(729): 69
05-28 00:38:04.241: INFO/KKKKKKKKKK============(729): 70
05-28 00:38:04.241: INFO/KKKKKKKKKK============(729): 71
05-28 00:38:04.261: INFO/KKKKKKKKKK============(729): 72
05-28 00:38:04.261: INFO/KKKKKKKKKK============(729): 73
05-28 00:38:04.261: INFO/KKKKKKKKKK============(729): 74
05-28 00:38:04.270: INFO/KKKKKKKKKK============(729): 75
05-28 00:38:04.270: INFO/KKKKKKKKKK============(729): 76
05-28 00:38:04.270: INFO/KKKKKKKKKK============(729): 77
05-28 00:38:04.281: INFO/KKKKKKKKKK============(729): 78
05-28 00:38:04.291: INFO/KKKKKKKKKK============(729): 79
05-28 00:38:04.291: INFO/KKKKKKKKKK============(729): 80
05-28 00:38:04.301: INFO/>>>>>>>>>>>>>>>>while<<<<<<<<<<<<<<<<(729): >>>>>>>>>>>>>>>>>>>loop == true????
到此就不循环了